Stauroneis schinzii var. argentina Frenguelli

Vouilloud, A. A., Guerrero, J. M., Palladino, M. B. & Lamaro, A. A., 2021, Revision Of The Type Materials Of Stauroneis Schinzii Var. Argentina Frenguelli And S. Schinzii Var. Maxima Frenguelli (Bacillariophyceae), Phytotaxa 478 (1), pp. 119-130 : 127

Stauroneis schinzii var. argentina Frenguelli emend Guerrero & Vouilloud

Emended diagnosis: Valves linear, 112–156 µm length and 13.8–15.5 µm width, slightly widened in the middle, with ends rounded and broadly rostrate. Pseudosepta absent. Axial area straight, moderately wide and bordered by irregularly long striae. Central area expanded into a relatively narrow stauros, moderately broadening to the margins. Raphe oblique, filiform towards the ends, laying between two internal longitudinal thickenings; external proximal endings drop-like expanded and deflected to one side, internally indistinct; distal fissures extended onto the valve mantle and hooked. Striae uniseriate, 14–16 in 10 µm, radiate at the centre and slightly radiate to parallel towards the poles; areolae rounded or transapically elongated, 15–22 in 10 µm, continuous onto the valve mantle.